Compressor hydraulicin

[JONSY]

Hello Everyone,

I`m am back again with my list of problems that I am hoping somebody may have some knowledge to share on. Basicly I have two Sabroe`s on a pack with a common separator. The Sabroe compressors are the SAB 163 HF running on an Ammonia system with Surge drum, economiser, Evaps , condensor, liquid pumps and reciever. The one compressors appears to runs fine, but when our other compressor has run and it has carried over about 100 litres of oil into the fridge system which we have to replace into the separator.We have thought that maybe the oil separator filter is blocked, but the fault only happens on the one compressor which rules that out. Also the Sabroe kicked out on Capacity error and once reset and run the compressor spun up with too much oil in the crankcase and sounded like it was hydraulicin, I am hoping that perhaps there is a solenoid or oil filter that is not functioning correctly. Does anyone have any previous experience that may point me in the right direction with this fault?
Many thanks, Jonsy.

[Grizzly]

Hi Jonsy
I have Several general questions, are you using a Unisab 2 controller.
If so approx how long does the compressor run before it trips out out on capacity Error.
From memory if the Unisab does not see any slide movement for say 20mins (set in Unisab).
It will assume there is a problem and shut down on Capacity error.

How long have you had this issue?

Has anyone changed or replaced anything on the comp recently?

In other words is there any historic maintenance that coincides with the development of this issue.

When were the coalescers last checked, the state of the one nearest the errant comp may be relevant.
in fact how many run hours do the comps have?

Does this comp use a side load economizer?

Is the oil return line needle valve set up correctly?

Also as I think you may suspect, you could have a shot "O" ring within the capacity regulating cylinder.
(basically this drives the slide valve) does the Unisab show the comps load capacity changing whilst it is running?
How smooth is it's operation if it does?


Lastly may I suggest you phone the UK Sabroe Technical guys as they are extremely knowledgeable and Helpful.
And they are there to help sort Sabroe issues for Sabroe users!
I am assuming that you are in the UK?
Grizzly

[Magoo]

All the above as suggested by Grizzly,
add, check discharge stop check is not passing in off cycle, and oil injection solenoid is not passing in off cycle. That hydraulic noise at startup is not good and indicates a screw filled with oil or refrigerant and oil, which in turn takes the oil separator way out side normal velocity designs and can carry oil into system